Strength and microstructure of semi-solid stirring brazing of SiCp/A356 composites and aluminum alloy in air

Chongqing University of Technology, No. 69, Hongguang Road, Chongqing 400054, P.R. China

Adv. Mater. Lett., 2011, 2 (3), pp 233-238

DOI: 10.5185/amlett.2011.1216

Publication Date (Web): Apr 08, 2012

Copyright © IAAM-VBRI Press

E-mail: hbxu@cqut.edu.cn, luoquanxiang@cqut.edu.cn  

Abstract

The semi-solid stirring brazing process of SiC_p/A356 composites and 2024 aluminum alloy was investigated. The two substrates were heated up to the semisolid temperature range of Zn₂₇Al filler metal in the joint region by a resistance heating plate in air. At this point a stirrer was penetrated into the semi-solid weld seam in order to mix filler metal and the two sides of substrates into a single uniform joint. After stirring, specimens were sectioned for analysis of macro- and micro-structures along the weld region. The research shows that SiC_p/A356 composites and aluminum alloy can be successfully joined with semi-solid filler metal by optimizing stirring temperature. It can be found that most of the oxide film on the surface of the base metal was disrupted and removed through the observation by SEM. The metallurgical bonds formed between the filler metal and the base materials. Since the semisolid temperature range of filler metal is narrow, the accurate controlling of weld pool temperature must be considered.

Keywords

Aluminum metal-matrix composites, 2024 aluminum alloy, brazing, stirring, semi-solid